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ruby--ruby/signal.c
akr 73c5a99b50 * signal.c (ruby_signal): don't set SA_RESTART.
[ruby-dev:26276]


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@8567 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
2005-06-05 01:26:01 +00:00

1003 lines
20 KiB
C

/**********************************************************************
signal.c -
$Author$
$Date$
created at: Tue Dec 20 10:13:44 JST 1994
Copyright (C) 1993-2003 Yukihiro Matsumoto
Copyright (C) 2000 Network Applied Communication Laboratory, Inc.
Copyright (C) 2000 Information-technology Promotion Agency, Japan
**********************************************************************/
#include "ruby.h"
#include "rubysig.h"
#include <signal.h>
#include <stdio.h>
#ifdef __BEOS__
#undef SIGBUS
#endif
#ifndef NSIG
# ifdef DJGPP
# define NSIG SIGMAX
# else
# define NSIG (_SIGMAX + 1) /* For QNX */
# endif
#endif
static struct signals {
char *signm;
int signo;
} siglist [] = {
#ifdef SIGHUP
{"HUP", SIGHUP},
#endif
{"INT", SIGINT},
#ifdef SIGQUIT
{"QUIT", SIGQUIT},
#endif
#ifdef SIGILL
{"ILL", SIGILL},
#endif
#ifdef SIGTRAP
{"TRAP", SIGTRAP},
#endif
#ifdef SIGIOT
{"IOT", SIGIOT},
#endif
#ifdef SIGABRT
{"ABRT", SIGABRT},
#endif
#ifdef SIGEMT
{"EMT", SIGEMT},
#endif
#ifdef SIGFPE
{"FPE", SIGFPE},
#endif
#ifdef SIGKILL
{"KILL", SIGKILL},
#endif
#ifdef SIGBUS
{"BUS", SIGBUS},
#endif
#ifdef SIGSEGV
{"SEGV", SIGSEGV},
#endif
#ifdef SIGSYS
{"SYS", SIGSYS},
#endif
#ifdef SIGPIPE
{"PIPE", SIGPIPE},
#endif
#ifdef SIGALRM
{"ALRM", SIGALRM},
#endif
#ifdef SIGTERM
{"TERM", SIGTERM},
#endif
#ifdef SIGURG
{"URG", SIGURG},
#endif
#ifdef SIGSTOP
{"STOP", SIGSTOP},
#endif
#ifdef SIGTSTP
{"TSTP", SIGTSTP},
#endif
#ifdef SIGCONT
{"CONT", SIGCONT},
#endif
#ifdef SIGCHLD
{"CHLD", SIGCHLD},
#endif
#ifdef SIGCLD
{"CLD", SIGCLD},
#else
# ifdef SIGCHLD
{"CLD", SIGCHLD},
# endif
#endif
#ifdef SIGTTIN
{"TTIN", SIGTTIN},
#endif
#ifdef SIGTTOU
{"TTOU", SIGTTOU},
#endif
#ifdef SIGIO
{"IO", SIGIO},
#endif
#ifdef SIGXCPU
{"XCPU", SIGXCPU},
#endif
#ifdef SIGXFSZ
{"XFSZ", SIGXFSZ},
#endif
#ifdef SIGVTALRM
{"VTALRM", SIGVTALRM},
#endif
#ifdef SIGPROF
{"PROF", SIGPROF},
#endif
#ifdef SIGWINCH
{"WINCH", SIGWINCH},
#endif
#ifdef SIGUSR1
{"USR1", SIGUSR1},
#endif
#ifdef SIGUSR2
{"USR2", SIGUSR2},
#endif
#ifdef SIGLOST
{"LOST", SIGLOST},
#endif
#ifdef SIGMSG
{"MSG", SIGMSG},
#endif
#ifdef SIGPWR
{"PWR", SIGPWR},
#endif
#ifdef SIGPOLL
{"POLL", SIGPOLL},
#endif
#ifdef SIGDANGER
{"DANGER", SIGDANGER},
#endif
#ifdef SIGMIGRATE
{"MIGRATE", SIGMIGRATE},
#endif
#ifdef SIGPRE
{"PRE", SIGPRE},
#endif
#ifdef SIGGRANT
{"GRANT", SIGGRANT},
#endif
#ifdef SIGRETRACT
{"RETRACT", SIGRETRACT},
#endif
#ifdef SIGSOUND
{"SOUND", SIGSOUND},
#endif
#ifdef SIGINFO
{"INFO", SIGINFO},
#endif
{NULL, 0}
};
static int
signm2signo(nm)
char *nm;
{
struct signals *sigs;
for (sigs = siglist; sigs->signm; sigs++)
if (strcmp(sigs->signm, nm) == 0)
return sigs->signo;
return 0;
}
static char*
signo2signm(no)
int no;
{
struct signals *sigs;
for (sigs = siglist; sigs->signm; sigs++)
if (sigs->signo == no)
return sigs->signm;
return 0;
}
const char *
ruby_signal_name(no)
int no;
{
return signo2signm(no);
}
/*
* call-seq:
* Process.kill(signal, pid, ...) => fixnum
*
* Sends the given signal to the specified process id(s), or to the
* current process if _pid_ is zero. _signal_ may be an
* integer signal number or a POSIX signal name (either with or without
* a +SIG+ prefix). If _signal_ is negative (or starts
* with a minus sign), kills process groups instead of
* processes. Not all signals are available on all platforms.
*
* pid = fork do
* Signal.trap("HUP") { puts "Ouch!"; exit }
* # ... do some work ...
* end
* # ...
* Process.kill("HUP", pid)
* Process.wait
*
* <em>produces:</em>
*
* Ouch!
*/
VALUE
rb_f_kill(argc, argv)
int argc;
VALUE *argv;
{
int negative = 0;
int sig;
int i;
char *s;
rb_secure(2);
if (argc < 2)
rb_raise(rb_eArgError, "wrong number of arguments -- kill(sig, pid...)");
switch (TYPE(argv[0])) {
case T_FIXNUM:
sig = FIX2INT(argv[0]);
break;
case T_SYMBOL:
s = rb_id2name(SYM2ID(argv[0]));
if (!s) rb_raise(rb_eArgError, "bad signal");
goto str_signal;
case T_STRING:
s = RSTRING(argv[0])->ptr;
if (s[0] == '-') {
negative++;
s++;
}
str_signal:
if (strncmp("SIG", s, 3) == 0)
s += 3;
if((sig = signm2signo(s)) == 0)
rb_raise(rb_eArgError, "unsupported name `SIG%s'", s);
if (negative)
sig = -sig;
break;
default:
{
VALUE str;
str = rb_check_string_type(argv[0]);
if (!NIL_P(str)) {
s = RSTRING(str)->ptr;
goto str_signal;
}
rb_raise(rb_eArgError, "bad signal type %s",
rb_obj_classname(argv[0]));
}
break;
}
if (sig < 0) {
sig = -sig;
for (i=1; i<argc; i++) {
int pid = NUM2INT(argv[i]);
#ifdef HAS_KILLPG
if (killpg(pid, sig) < 0)
#else
if (kill(-pid, sig) < 0)
#endif
rb_sys_fail(0);
}
}
else {
for (i=1; i<argc; i++) {
Check_Type(argv[i], T_FIXNUM);
if (kill(FIX2INT(argv[i]), sig) < 0)
rb_sys_fail(0);
}
}
return INT2FIX(i-1);
}
static struct {
VALUE cmd;
int safe;
} trap_list[NSIG];
static rb_atomic_t trap_pending_list[NSIG];
static char rb_trap_accept_nativethreads[NSIG];
rb_atomic_t rb_trap_pending;
rb_atomic_t rb_trap_immediate;
int rb_prohibit_interrupt = 1;
void
rb_gc_mark_trap_list()
{
#ifndef MACOS_UNUSE_SIGNAL
int i;
for (i=0; i<NSIG; i++) {
if (trap_list[i].cmd)
rb_gc_mark(trap_list[i].cmd);
}
#endif /* MACOS_UNUSE_SIGNAL */
}
#ifdef __dietlibc__
#define sighandler_t sh_t
#endif
typedef RETSIGTYPE (*sighandler_t)_((int));
#ifdef POSIX_SIGNAL
static sighandler_t
ruby_signal(signum, handler)
int signum;
sighandler_t handler;
{
struct sigaction sigact, old;
rb_trap_accept_nativethreads[signum] = 0;
sigact.sa_handler = handler;
sigemptyset(&sigact.sa_mask);
sigact.sa_flags = 0;
#ifdef SA_NOCLDWAIT
if (signum == SIGCHLD && handler == SIG_IGN)
sigact.sa_flags |= SA_NOCLDWAIT;
#endif
sigaction(signum, &sigact, &old);
return old.sa_handler;
}
void
posix_signal(signum, handler)
int signum;
sighandler_t handler;
{
ruby_signal(signum, handler);
}
#ifdef HAVE_NATIVETHREAD
static sighandler_t
ruby_nativethread_signal(signum, handler)
int signum;
sighandler_t handler;
{
sighandler_t old;
old = ruby_signal(signum, handler);
rb_trap_accept_nativethreads[signum] = 1;
return old;
}
void
posix_nativethread_signal(signum, handler)
int signum;
sighandler_t handler;
{
ruby_nativethread_signal(signum, handler);
}
#endif
#else /* !POSIX_SIGNAL */
#define ruby_signal(sig,handler) (rb_trap_accept_nativethreads[sig] = 0, signal((sig),(handler)))
#ifdef HAVE_NATIVETHREAD
static sighandler_t
ruby_nativethread_signal(signum, handler)
int signum;
sighandler_t handler;
{
sighandler_t old;
old = signal(signum, handler);
rb_trap_accept_nativethreads[signum] = 1;
return old;
}
#endif
#endif
static void signal_exec _((int sig));
static void
signal_exec(sig)
int sig;
{
if (trap_list[sig].cmd == 0) {
switch (sig) {
case SIGINT:
rb_thread_interrupt();
break;
#ifdef SIGHUP
case SIGHUP:
#endif
#ifdef SIGQUIT
case SIGQUIT:
#endif
#ifdef SIGALRM
case SIGALRM:
#endif
#ifdef SIGUSR1
case SIGUSR1:
#endif
#ifdef SIGUSR2
case SIGUSR2:
#endif
rb_thread_signal_raise(signo2signm(sig));
break;
}
}
else {
rb_thread_trap_eval(trap_list[sig].cmd, sig, trap_list[sig].safe);
}
}
static void
sigsend_to_ruby_thread(sig)
int sig;
{
#ifdef HAVE_NATIVETHREAD_KILL
# ifdef HAVE_SIGPROCMASK
sigset_t mask, old_mask;
# else
int mask, old_mask;
# endif
#ifdef HAVE_SIGPROCMASK
sigfillset(&mask);
sigprocmask(SIG_BLOCK, &mask, &old_mask);
#else
mask = sigblock(~0);
sigsetmask(mask);
#endif
ruby_native_thread_kill(sig);
#endif
}
static RETSIGTYPE sighandler _((int));
static RETSIGTYPE
sighandler(sig)
int sig;
{
#ifdef _WIN32
#define IN_MAIN_CONTEXT(f, a) (rb_w32_main_context(a, f) ? (void)0 : f(a))
#else
#define IN_MAIN_CONTEXT(f, a) f(a)
#endif
if (sig >= NSIG) {
rb_bug("trap_handler: Bad signal %d", sig);
}
#if defined(HAVE_NATIVETHREAD) && defined(HAVE_NATIVETHREAD_KILL)
if (!is_ruby_native_thread() && !rb_trap_accept_nativethreads[sig]) {
sigsend_to_ruby_thread(sig);
return;
}
#endif
#if !defined(BSD_SIGNAL) && !defined(POSIX_SIGNAL)
if (rb_trap_accept_nativethreads[sig]) {
ruby_nativethread_signal(sig, sighandler);
} else {
ruby_signal(sig, sighandler);
}
#endif
if (trap_list[sig].cmd == 0 && ATOMIC_TEST(rb_trap_immediate)) {
IN_MAIN_CONTEXT(signal_exec, sig);
ATOMIC_SET(rb_trap_immediate, 1);
}
else {
ATOMIC_INC(rb_trap_pending);
ATOMIC_INC(trap_pending_list[sig]);
}
}
#ifdef SIGBUS
static RETSIGTYPE sigbus _((int));
static RETSIGTYPE
sigbus(sig)
int sig;
{
#if defined(HAVE_NATIVETHREAD) && defined(HAVE_NATIVETHREAD_KILL)
if (!is_ruby_native_thread() && !rb_trap_accept_nativethreads[sig]) {
sigsend_to_ruby_thread(sig);
return;
}
#endif
rb_bug("Bus Error");
}
#endif
#ifdef SIGSEGV
static RETSIGTYPE sigsegv _((int));
static RETSIGTYPE
sigsegv(sig)
int sig;
{
#if defined(HAVE_NATIVETHREAD) && defined(HAVE_NATIVETHREAD_KILL)
if (!is_ruby_native_thread() && !rb_trap_accept_nativethreads[sig]) {
sigsend_to_ruby_thread(sig);
return;
}
#endif
rb_bug("Segmentation fault");
}
#endif
#ifdef SIGPIPE
static RETSIGTYPE sigpipe _((int));
static RETSIGTYPE
sigpipe(sig)
int sig;
{
/* do nothing */
}
#endif
void
rb_trap_exit()
{
#ifndef MACOS_UNUSE_SIGNAL
if (trap_list[0].cmd) {
VALUE trap_exit = trap_list[0].cmd;
trap_list[0].cmd = 0;
rb_eval_cmd(trap_exit, rb_ary_new3(1, INT2FIX(0)), trap_list[0].safe);
}
#endif
}
void
rb_trap_exec()
{
#ifndef MACOS_UNUSE_SIGNAL
int i;
for (i=0; i<NSIG; i++) {
if (trap_pending_list[i]) {
trap_pending_list[i] = 0;
signal_exec(i);
}
}
#endif /* MACOS_UNUSE_SIGNAL */
rb_trap_pending = 0;
}
struct trap_arg {
#ifndef _WIN32
# ifdef HAVE_SIGPROCMASK
sigset_t mask;
# else
int mask;
# endif
#endif
VALUE sig, cmd;
};
# ifdef HAVE_SIGPROCMASK
static sigset_t trap_last_mask;
# else
static int trap_last_mask;
# endif
static RETSIGTYPE sigexit _((int));
static RETSIGTYPE
sigexit(sig)
int sig;
{
#if defined(HAVE_NATIVETHREAD) && defined(HAVE_NATIVETHREAD_KILL)
if (!is_ruby_native_thread() && !rb_trap_accept_nativethreads[sig]) {
sigsend_to_ruby_thread(sig);
return;
}
#endif
rb_exit(0);
}
static VALUE
trap(arg)
struct trap_arg *arg;
{
sighandler_t func, oldfunc;
VALUE command, oldcmd;
int sig = -1;
char *s;
func = sighandler;
command = arg->cmd;
if (NIL_P(command)) {
func = SIG_IGN;
}
else if (TYPE(command) == T_STRING) {
SafeStringValue(command); /* taint check */
if (RSTRING(command)->len == 0) {
func = SIG_IGN;
}
else if (RSTRING(command)->len == 7) {
if (strncmp(RSTRING(command)->ptr, "SIG_IGN", 7) == 0) {
func = SIG_IGN;
}
else if (strncmp(RSTRING(command)->ptr, "SIG_DFL", 7) == 0) {
func = SIG_DFL;
}
else if (strncmp(RSTRING(command)->ptr, "DEFAULT", 7) == 0) {
func = SIG_DFL;
}
}
else if (RSTRING(command)->len == 6) {
if (strncmp(RSTRING(command)->ptr, "IGNORE", 6) == 0) {
func = SIG_IGN;
}
}
else if (RSTRING(command)->len == 4) {
if (strncmp(RSTRING(command)->ptr, "EXIT", 4) == 0) {
func = sigexit;
}
}
}
if (func == SIG_IGN || func == SIG_DFL) {
command = 0;
}
switch (TYPE(arg->sig)) {
case T_FIXNUM:
sig = FIX2INT(arg->sig);
break;
case T_SYMBOL:
s = rb_id2name(SYM2ID(arg->sig));
if (!s) rb_raise(rb_eArgError, "bad signal");
goto str_signal;
case T_STRING:
s = RSTRING(arg->sig)->ptr;
str_signal:
if (strncmp("SIG", s, 3) == 0)
s += 3;
sig = signm2signo(s);
if (sig == 0 && strcmp(s, "EXIT") != 0)
rb_raise(rb_eArgError, "unsupported signal SIG%s", s);
}
if (sig < 0 || sig > NSIG) {
rb_raise(rb_eArgError, "invalid signal number (%d)", sig);
}
#if defined(HAVE_SETITIMER)
if (sig == SIGVTALRM) {
rb_raise(rb_eArgError, "SIGVTALRM reserved for Thread; can't set handler");
}
#endif
if (func == SIG_DFL) {
switch (sig) {
case SIGINT:
#ifdef SIGHUP
case SIGHUP:
#endif
#ifdef SIGQUIT
case SIGQUIT:
#endif
#ifdef SIGALRM
case SIGALRM:
#endif
#ifdef SIGUSR1
case SIGUSR1:
#endif
#ifdef SIGUSR2
case SIGUSR2:
#endif
func = sighandler;
break;
#ifdef SIGBUS
case SIGBUS:
func = sigbus;
break;
#endif
#ifdef SIGSEGV
case SIGSEGV:
func = sigsegv;
break;
#endif
#ifdef SIGPIPE
case SIGPIPE:
func = sigpipe;
break;
#endif
}
}
oldfunc = ruby_signal(sig, func);
oldcmd = trap_list[sig].cmd;
if (!oldcmd) {
if (oldfunc == SIG_IGN) oldcmd = rb_str_new2("IGNORE");
else if (oldfunc == sighandler) oldcmd = rb_str_new2("DEFAULT");
else oldcmd = Qnil;
}
trap_list[sig].cmd = command;
trap_list[sig].safe = ruby_safe_level;
/* enable at least specified signal. */
#ifndef _WIN32
#ifdef HAVE_SIGPROCMASK
sigdelset(&arg->mask, sig);
#else
arg->mask &= ~sigmask(sig);
#endif
#endif
return oldcmd;
}
#ifndef _WIN32
static VALUE
trap_ensure(arg)
struct trap_arg *arg;
{
/* enable interrupt */
#ifdef HAVE_SIGPROCMASK
sigprocmask(SIG_SETMASK, &arg->mask, NULL);
#else
sigsetmask(arg->mask);
#endif
trap_last_mask = arg->mask;
return 0;
}
#endif
void
rb_trap_restore_mask()
{
#ifndef _WIN32
# ifdef HAVE_SIGPROCMASK
sigprocmask(SIG_SETMASK, &trap_last_mask, NULL);
# else
sigsetmask(trap_last_mask);
# endif
#endif
}
/*
* call-seq:
* Signal.trap( signal, proc ) => obj
* Signal.trap( signal ) {| | block } => obj
*
* Specifies the handling of signals. The first parameter is a signal
* name (a string such as ``SIGALRM'', ``SIGUSR1'', and so on) or a
* signal number. The characters ``SIG'' may be omitted from the
* signal name. The command or block specifies code to be run when the
* signal is raised. If the command is the string ``IGNORE'' or
* ``SIG_IGN'', the signal will be ignored. If the command is
* ``DEFAULT'' or ``SIG_DFL'', the operating system's default handler
* will be invoked. If the command is ``EXIT'', the script will be
* terminated by the signal. Otherwise, the given command or block
* will be run.
* The special signal name ``EXIT'' or signal number zero will be
* invoked just prior to program termination.
* trap returns the previous handler for the given signal.
*
* Signal.trap(0, proc { puts "Terminating: #{$$}" })
* Signal.trap("CLD") { puts "Child died" }
* fork && Process.wait
*
* produces:
* Terminating: 27461
* Child died
* Terminating: 27460
*/
static VALUE
sig_trap(argc, argv)
int argc;
VALUE *argv;
{
struct trap_arg arg;
rb_secure(2);
if (argc == 0 || argc > 2) {
rb_raise(rb_eArgError, "wrong number of arguments -- trap(sig, cmd)/trap(sig){...}");
}
arg.sig = argv[0];
if (argc == 1) {
arg.cmd = rb_block_proc();
}
else if (argc == 2) {
arg.cmd = argv[1];
}
if (OBJ_TAINTED(arg.cmd)) {
rb_raise(rb_eSecurityError, "Insecure: tainted signal trap");
}
#ifndef _WIN32
/* disable interrupt */
# ifdef HAVE_SIGPROCMASK
sigfillset(&arg.mask);
sigprocmask(SIG_BLOCK, &arg.mask, &arg.mask);
# else
arg.mask = sigblock(~0);
# endif
return rb_ensure(trap, (VALUE)&arg, trap_ensure, (VALUE)&arg);
#else
return trap(&arg);
#endif
}
/*
* call-seq:
* Signal.list => a_hash
*
* Returns a list of signal names mapped to the corresponding
* underlying signal numbers.
*
* Signal.list #=> {"ABRT"=>6, "ALRM"=>14, "BUS"=>7, "CHLD"=>17, "CLD"=>17, "CONT"=>18, "FPE"=>8, "HUP"=>1, "ILL"=>4, "INT"=>2, "IO"=>29, "IOT"=>6, "KILL"=>9, "PIPE"=>13, "POLL"=>29, "PROF"=>27, "PWR"=>30, "QUIT"=>3, "SEGV"=>11, "STOP"=>19, "SYS"=>31, "TERM"=>15, "TRAP"=>5, "TSTP"=>20, "TTIN"=>21, "TTOU"=>22, "URG"=>23, "USR1"=>10, "USR2"=>12, "VTALRM"=>26, "WINCH"=>28, "XCPU"=>24, "XFSZ"=>25}
*/
static VALUE
sig_list()
{
VALUE h = rb_hash_new();
struct signals *sigs;
for (sigs = siglist; sigs->signm; sigs++) {
rb_hash_aset(h, rb_str_new2(sigs->signm), INT2FIX(sigs->signo));
}
return h;
}
static void
install_sighandler(signum, handler)
int signum;
sighandler_t handler;
{
sighandler_t old;
old = ruby_signal(signum, handler);
if (old != SIG_DFL) {
ruby_signal(signum, old);
}
}
#ifdef HAVE_NATIVETHREAD
static void
install_nativethread_sighandler(signum, handler)
int signum;
sighandler_t handler;
{
sighandler_t old;
int old_st;
old_st = rb_trap_accept_nativethreads[signum];
old = ruby_nativethread_signal(signum, handler);
if (old != SIG_DFL) {
if (old_st) {
ruby_nativethread_signal(signum, old);
} else {
ruby_signal(signum, old);
}
}
}
#endif
static void
init_sigchld(sig)
int sig;
{
sighandler_t oldfunc;
#ifndef _WIN32
# ifdef HAVE_SIGPROCMASK
sigset_t mask;
# else
int mask;
# endif
#endif
#ifndef _WIN32
/* disable interrupt */
# ifdef HAVE_SIGPROCMASK
sigfillset(&mask);
sigprocmask(SIG_BLOCK, &mask, &mask);
# else
mask = sigblock(~0);
# endif
#endif
oldfunc = ruby_signal(sig, SIG_DFL);
if (oldfunc != SIG_DFL && oldfunc != SIG_IGN) {
ruby_signal(sig, oldfunc);
} else {
trap_list[sig].cmd = 0;
}
#ifndef _WIN32
#ifdef HAVE_SIGPROCMASK
sigdelset(&mask, sig);
sigprocmask(SIG_SETMASK, &mask, NULL);
#else
mask &= ~sigmask(sig);
sigsetmask(mask);
#endif
trap_last_mask = mask;
#endif
}
/*
* Many operating systems allow signals to be sent to running
* processes. Some signals have a defined effect on the process, while
* others may be trapped at the code level and acted upon. For
* example, your process may trap the USR1 signal and use it to toggle
* debugging, and may use TERM to initiate a controlled shutdown.
*
* pid = fork do
* Signal.trap("USR1") do
* $debug = !$debug
* puts "Debug now: #$debug"
* end
* Signal.trap("TERM") do
* puts "Terminating..."
* shutdown()
* end
* # . . . do some work . . .
* end
*
* Process.detach(pid)
*
* # Controlling program:
* Process.kill("USR1", pid)
* # ...
* Process.kill("USR1", pid)
* # ...
* Process.kill("TERM", pid)
*
* produces:
* Debug now: true
* Debug now: false
* Terminating...
*
* The list of available signal names and their interpretation is
* system dependent. Signal delivery semantics may also vary between
* systems; in particular signal delivery may not always be reliable.
*/
void
Init_signal()
{
#ifndef MACOS_UNUSE_SIGNAL
VALUE mSignal = rb_define_module("Signal");
rb_define_global_function("trap", sig_trap, -1);
rb_define_module_function(mSignal, "trap", sig_trap, -1);
rb_define_module_function(mSignal, "list", sig_list, 0);
install_sighandler(SIGINT, sighandler);
#ifdef SIGHUP
install_sighandler(SIGHUP, sighandler);
#endif
#ifdef SIGQUIT
install_sighandler(SIGQUIT, sighandler);
#endif
#ifdef SIGALRM
install_sighandler(SIGALRM, sighandler);
#endif
#ifdef SIGUSR1
install_sighandler(SIGUSR1, sighandler);
#endif
#ifdef SIGUSR2
install_sighandler(SIGUSR2, sighandler);
#endif
#ifdef SIGBUS
install_sighandler(SIGBUS, sigbus);
#endif
#ifdef SIGSEGV
install_sighandler(SIGSEGV, sigsegv);
#endif
#ifdef SIGPIPE
install_sighandler(SIGPIPE, sigpipe);
#endif
#ifdef SIGCLD
init_sigchld(SIGCLD);
#endif
#ifdef SIGCHLD
init_sigchld(SIGCHLD);
#endif
#endif /* MACOS_UNUSE_SIGNAL */
}